Field
Embodiments of the present invention generally relates to a method and apparatus for fabricating devices on a semiconductor substrate. More particularly, embodiments of the present invention provide method and apparatus for heating and supporting a substrate in a processing chamber.
Description of the Related Art
During manufacturing of semiconductor devices, a substrate is usually processed in a processing chamber, where deposition, etching, thermal processing may be performed to the substrate.
A semiconductor processing chamber generally includes a chamber body defining an inner volume for processing a substrate. A substrate support is usually disposed in the inner volume to support the substrate during processing. Sometimes, when the process requires the substrate to be at an elevated temperature, a heated substrate support is generally used in a processing chamber.
A heated substrate support usually includes a substrate supporting plate for supporting and heating a substrate. When heated, the substrate supporting plate may be at a very high temperature. But it is generally desirable to keep the chamber body cool during processing. To prevent the substrate supporting plate from heating the chamber body, the substrate supporting plate is usually positioned at a distance from the chamber body and does not contact the chamber body. A pedestal design having a supporting column extending from a center back of the substrate supporting plate is usually to position the substrate supporting plate away from the chamber body. The column provides structural support to the substrate supporting plate and also provides a passage for wirings to the substrate supporting surface. Generally, the column extends down and out of the processing volume through a bottom wall of the chamber body.
However, the traditional heated substrate supports described above requires relative large inner volume in a processing chamber and is not practical for any processing chamber. Particularly, when a chamber volume is small or it is not desirable to form a center opening through the bottom wall of the chamber body, traditional heated substrate supports are not applicable.
Therefore, there is a need for methods and apparatus for heating and supporting a substrate in a small chamber.